MARS SURVEYOR 98 MISSION STATUS

In-flight checkout of the "all-stellar" attitude determination and
control system is now complete! The all-stellar attitude determination
software was successfully exercised last Friday (Jun. 11) onboard the
spacecraft, with the full flight team monitoring the vehicle's performance
on the ground. On Wednesday, Jun. 16, the final step in the checkout
process was conducted, in which the orbiter's autopilot was allowed to
control the spacecraft using outputs from the all-stellar system. The
autopilot's performance equalled or exceeded expectations in all respects.

Last week the flight team successfully completed the "end-to-end" test of
the early surface mission through the second Martian day following landing
(dubbed "Sol 1") using both the MPL and MCO simulators. The team is now
preparing a simulator test of the Entry/Descent/Landing (EDL) master
sequence early next week; the master sequence performs all of the tasks
needed to configure the spacecraft for entry, finishing with the commands
which activite the onboard guidance system that controls the spacecraft
from several minutes prior to entry through touchdown.